安装Pillow库，用于生成图形验证码：pip install Pillow
字体文件来源
生成一个验证码图片
import randomimport stringfrom PIL import Image, ImageDraw, ImageFont# Image：一个画布# ImageDraw：一个画笔# ImageFont:画笔的字体class Captcha(object): """ 生成图形验证码 """ number = 4 # 生成几位数的验证码 size = (100, 30) # 验证码图片的宽度和高度 fontsize = 25 # 验证码字体大小 line_number = 2 # 加入干扰线的条数 # 构建一个验证码源文本 SOURCE = list(string.ascii_letters) for index in range(0, 10): SOURCE.append(str(index)) # 用来绘制干扰线 @classmethod def __gene_line(cls, draw, width, height): begin = (random.randint(0, width), random.randint(0, height)) end = (random.randint(0, width), random.randint(0, height)) draw.line([begin, end], fill=cls.__gene_random_color(), width=2) # 用来绘制干扰点 @classmethod def __gene_points(cls, draw, point_chance, width, height): chance = min(100, max(0, int(point_chance))) # 大小限制在[0, 100] for w in range(width): for h in range(height): tmp = random.randint(0, 100) if tmp > 100 - chance: draw.point((w, h), fill=cls.__gene_random_color()) # 生成随机的颜色 @classmethod def __gene_random_color(cls, start=0, end=255): random.seed() return (random.randint(start, end), random.randint(start, end), random.randint(start, end)) # 随机选择一个字体 @classmethod def __gene_random_font(cls): fonts = [ 'Courgette-Regular.ttf', 'LHANDW.TTF', 'Lobster-Regular.ttf', 'verdana.ttf' ] font = random.choice(fonts) return 'utils/captcha/' + font # 返回字体路径 # 用来随机生成一个字符串(包括英文和数字) @classmethod def gene_text(cls, number): # number是生成验证码的位数 return ''.join(random.sample(cls.SOURCE, number)) # 生成验证码 @classmethod def gene_graph_captcha(cls): width, height = cls.size # 验证码图片的宽和高 # 创建图片 # R：Red（红色）0-255 # G：G（绿色）0-255 # B：B（蓝色）0-255 # A：Alpha（透明度） image = Image.new('RGBA', (width, height), cls.__gene_random_color(0, 100)) font = ImageFont.truetype(cls.__gene_random_font(), cls.fontsize) # 验证码的字体 draw = ImageDraw.Draw(image) # 创建画笔 text = cls.gene_text(cls.number) # 生成字符串 font_width, font_height = font.getsize(text) # 获取字体的尺寸 # 填充字符串 draw.text(((width - font_width) / 2, (height - font_height) / 2), text, font=font, fill=cls.__gene_random_color(150, 255)) # 绘制干扰线 for x in range(0, cls.line_number): cls.__gene_line(draw, width, height) cls.__gene_points(draw, 10, width, height) # 绘制噪点 # 保存到本地 with open('captcha.png', 'wb') as fp: image.save(fp) return (text, image)if __name__ == '__main__': Captcha.gene_graph_captcha()
写一个获取验证码的视图给前端调用
from io import BytesIOfrom flask import Blueprint, views, render_template, make_responsefrom utils.captcha import Captchabp = Blueprint("front", __name__)@bp.route('/captcha/')def graph_captcha(): """ 获取验证码 """ text, image = Captcha.gene_graph_captcha() out = BytesIO() # 二进制流 image.save(out, 'png') out.seek(0) resp = make_response(out.read()) # 二进制流读取出来放到响应对象中 resp.content_type = 'image/png' return resp
